Vacuum brake structure



July 19, 1938. BROWN 2,124,454

VACUUM BRAKE STRUCTURE Original Filed April 13, 1935 2 Sheets-Sheet l BRAKES |NVENTOR cleave 15. Brown A'ITORNEY3 Patented July 19, 1938 v UNITED STATES PATENT OFFICE vacuum BRAKE sranc'runn Application April 13, 1933, Serial No. 665,978

' Renewed March 19, 1937 11 Claims. (Cl. 121-465) This invention relates to improved vacuum brake structures for automobiles or for vehicles generally.

The objects of the invention are: First, to provide an. improvedcylinder structure with improved valve mechanism.

Second, to improve the valve mechanism by re ducing the number of parts and eliminating. th machine work thereon. I Further objects and advantages pertaining to details and economies of construction and operation will appear from the description to follow. Preferred embodiments of my invention are illustrated in the accompanying drawings, in l5 7 which: a v

Fig. 1 is a side elevation view of the essential parts of a brake mechanism embodying the fea tures of my invention, the supports for the same being indicated diagrammatically. Fig. 2 is an enlarged detail end'elevatlonof the :iacuumpower cylinder with the valve in posi- Fig. 3 is a detail sectional elevation view on the irregular plan indicated by irregular line 3-3 of Fig. 2, the valve structure being sectioned on the slightly oblique line and the cylinder part in vertical central section as shown, the valve vent open.

Fig. 41s an enlarged detail sectional view of the valve structure on the same plane as Fig. 3 with the valve to the vacuum connection open and the air vent closed. v

Fig. 5 is a detail sectional view taken on line 3-5 of Fig. 1. l

The parts will be identified by their numerals of reference which are the same in all the views.

l is the vacuum power cylinder. This is supported by a bracket 2 secured by bolt 2' to the head end of the cylinder and to. the frame 3 of the automobile. 5' is the brake-lever pivotally fulcru ned on the fixed crossshaft 6. 11s the brake rod to the rear brakes and 8 is the brake rod to the front brakes whichbrakes may be of any desired construction.

9 is the brake pedal lever also fulcrumed at 6 provided with a pedal Ill and with a lug II for engaging the brake lever 5 to actuate the same from the brake. pedal lever. The lug ll engages the edge of lever 5 as the brake pedal is de-' the brakes. The piston rod extends through the cylinder cover and is surrounded by a cup-like shell H in which the piston rod has considerable lateral movement due to the clearance in the left end of the piston, as illustrated in Fig. 3. The 5 cup supports dustfilter material i5 to. filter the dust from the air entering the cylinder. The cylinder cover is integral and a connection i6-extends therefrom to the engine manifold or other means for creating vacuum or suction for the 10 operation of the cylinder. This pipe of course might connect to a vacuum tank.

The coupling I! for connection it extends through a port opening in the end of the cylinder and is provided with a valve seat [8. An ad- 15 ditional valve seat I3 is formed by a struck-up portion of the cylinder head. A conical valve 20 fits into the valve seat It, and has a spherically formed seating portion conforming to a corresponding valve seat to permit rocking of the 20 same. A valve 2| fits into the valve seat l9, the

' contacting parts being spherical to seat and to permit of freedom of rocking movement.

Valves 20 and 2! are rigidly connected by an arm 22. Valves 20 and 2| and arm 22 are pref- 25 erably formed from a stamping in a single piece, although they may be otherwise produced. g Actuating lever 23 is secured to the valve 2| extending axially through the same and being retained in place by clamp nut 24. This lever is apertured 3o to embrace the coupling l1 and is guided thereby.

Spring 23' is interposed between the lever- 23 and the cylinder head, causing the same to tend to seat both of the said valves. In operation the upper end 'of lever 23 (see Fig. 3) is moved to- 5 ward or away from the cylinder.

. Dust cap' 25 surrounds the valves being provided with felt or fibrous filter material 26 to prevent dust enteringthe cylinder. Valve c onnecting rod 21 extends from the valve lever 23 40 to the auxiliary operating lever 28, see Fig. 1, being pivoted at both ends. This auxiliary operating lever is fulcrumed at 23 at the lower end of the brake lever 5. Piston rod I3 is pivotally connected by a suitable yoke at 30 to the said 5 auxiliary lever 28, the relations of the pivots 23 and clearly appearing in Fig. 1. The same are slightly out of alinement with the axial line of piston rod IS, the pivot 30 being in the disposition there shown a little more elevated than 50 the pivot 29. The lever, 23 is a bent lever with ,the'bend toward the vacuum cylinder and the pivot 30 is at the bend of the lever and out of line with the ends of the lever. On the hub of the brake lever 9 is a short lever arm 3| which is connected at pivot 32 by a downwardly ex- 1 tending link 33 to the said pivot 30.

To explain operation of my improved brake,

. reference will be had to Fig. 1. When pressure is applied to the pedal Ill to depress the same, the lever 3 moves in a counterclockwise direction which swings the arm 3| upwardly in a counter 1 clockwise direction. This motion through the link a: swings the pivot to upwardly, swinging the upper end oi lever 28 to the left and pulling valve rod 21-to the left to open the. vacuum con trolling valve 13 swinging it from the position shown in Fig. 3 to the position shown in Fig. 4.

The piston rod l3, having considerable lateral movement, allows for this upward movement of the pivot 33 which is very slight. The opening of the valve 20 and the closing ofth'e valve 2| rod l3 to the right and the lever 5' and lever 23 move and tend to'overtake the short arm 3|. As

the short arm 3| isovertaken, the link 33 reacts thereagainst, pressing downwardly on the pivot 30 which swings the lever 23 ha clockwise direction which in turn moves the valve rod 21 to the right to close the valve 20 and stop the movement of the piston. This permits perfect control of the brake as it is held in any position corresponding to the position of the pedal. l0.

In the event that the powercyllnder fails, the brake lever 5 is actuaterd bythe lug I l' on the pedal lever 3 so that the brake can be applied by the foot. The lug I is ofl'setl'rom lever 3 to engage the edge of lever B so that as lever 9 is rotated by depression of pedal l0, the lug ll forces.

lever B in a counterclockwise direction, as viewed in Fig. 1. Also with the'preferred construction, the cylinder is of such dimensions as to partially do the work and cooperates withthe foot pedal in applying the brake, a small part of the work being done-by the work of the operator.

When the brake pedal I 0 is released or pressure is relieved on it, the brakespring I00 reacts to move the same toward the foot, the valve rod 21 is then pushed backwardly and the operation is repeated until the foot isentirely relieved when the valve swings to the position indicated in Fig. 3,-cutting ofl thevacuum and opening the cylinder vent, when the brake spring I00, which is here illustrated as connected to' the upper end of lever to pull the same in a clockwise direction, as

viewed in Fig, 1, but which maybe located elsewhere in any position to accomplish the release of the brakes, releases thebrake readily for a 2| to open and close at a faster rate than the vacuum admission valve 20. This operation re-' sults i'iom the fact that the pivotal connection of the lever arm to the rod 21 is closer to the vacuum admission port than ,the air admission port. This diil'erence in action enables the air admission valve-to quickly leave its seatupon rea lease of the brakes and atmospheric air rapidly fllls the cylinder 2 before the head of the piston. Quick release action is thus obtained. The provision of rigid connecting means between the valves 20 and 2| and the ability of thevalves and their respective valve seats to alternately function as fulcrums about which the leverage action takes place eliminates all valve lap or loss of movement between the time one or the other valve is. opened. The change of the fulcrum point from one valve to the other is practically instantaneous. Likewise, the complete closing of one valve and the commencement oitheopening of the other valve is practically instantaneous. Thus the valve control of inder in combination with a brake pedal lever .connected tooperate the brake in conjunction with the brake cylinder, I desire to state that my improved cylinder and valve can be manipulated in'any way and function to apply the brake without the auxiliary connecting feature.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: I

1. In an engine structure, a cylinder having a pair of ports, valves for said ports having inwardly facing seats of -a contour to seat spherical valves, rigidly connected valves of spherical contour adapted to fit said seats and pivot thereon, a lever having a rigid connection extending 1 through one of said ports and rigidly secured to the corresponding valve,.and means adapted to seat said valves, whereby on the actuation'of said lever, the valves will be opened and closed alternately, the closed valve serving as the fulcrum of the lever for the opening valve.

2. In an engine structure, .a cylinder having, a

for the opening valve.

3. In an engine structure, a cylinder having a pair of ports, said ports having inwardly facing seats, rigidly connected valves adapted to close outwardly and fit said seats, and a valve actuating lever means with 'an arm extending through one of said ports in operation and secured to the corresponding valve, adapted to open one valve while closing the other, the valves and seats alternately serving as fulcrums for said lever.

4. In an engine valve structure, .double having seats of a contour to seat spherical valves,

rigidly connected valves of spherical contour adapted to fit said seats and pivot thereon, and means for actuating said valves rigidly connected to one valve, whereby on the actuation of said valve actuating means the valves will be opened and closed alternately, the closed valve serving as a fulcrum for the opening valve.

5. In an engine valve structure, double ports q having seats of a contour to seat spherical valves,

rigidly connected valves of spherical contour adapted to fit said seats and pivot thereon, and

an arm connected to said valves and disposed through one of the ports and connected to act as a lever, whereby on the actuation of said valve actuating means the valves will be opened and closed alternately, the closed valve serving as a fulcrum for the opening valve.

6. Control mechanism for a cylinder comprising, in combination, a cylinder having a pair of adjacent ports, said ports having inwardly facing seats, rigidly connected valves adapted to close outwardly and fit said seats, and a valve actuating lever means with an arm extending through one of said ports in operation and secured to-the corresponding valve, adapted to open onevalve while closing the other, the valves and seats alternately serving as fulcrums for said lever, and means closer to one of said valves than the other for pivoting said-lever means whereby said valves are moved relative to their seats at different speeds for the same pivotal movement of said lever means.

'7. Valve control mechanism comprising, in

combination, a support having a pair of ports, said ports having .valve seats opening on one side of said support, a lever positioned on the opposite side of said support having a part thereof extending through one of said ports, a valve head on said part adapted upon movement of said lever in one direction to seat upon the valve seat of the port through which said part extends, a valve head engageable with the valve seat of said other port, and rigid means connecting said .valve heads together and adapted upon movement of said lever to cause said valve heads to alternately engage their respective valve seats and when thus in engagement to form a fulcrum about which said lever may be operated.

8. Valve control mechanism comprising, in

combination, a support having a pair of ports therethrough, said ports having valve seats openvalve heads whereby upon swinging movement of said lever arm the element is caused to alternately seat said valve heads upon their respective valve seats and when a valve head is thus seated to form a fulcrum about which the lever arm may be swung.

9. Valve control mechanism comprising, in combination, a support having a pair of ports, said ports having valve seats of a contour to'seat spherical valves, a pair of spherical valves, an element on one side of said support connecting said valves into a rigid unitary structure, and a lever arm on'the opposite side of said support having one end thereof bent and arranged to pass through one of said ports, and means rigidly connecting the bent end of said lever arm to said element.

10. Valve control mechanism comprising, in

combination, a wall having a pair of ports open-' ing therethrough, valve controlmeans for opening and closing said ports including a pair of valves on one side of said wall, means rigidly connecting said valves together, and valve actuating means including a lever arm'on the side of said wall opposite to said valves having a part passing through one of said ports and rigidly connected to said valve control means, said part forming the sole support for said control means including said pair of valves and adapted upon movement of said lever arm to alternately seat one or the other of said valves, the valves when each is thus seated forming a fulcrum about which the other valve may be swung as the lever is operated. I

11. In combination with a cylinder having an air admission portand a vacuum admission port, inside valve means for opening and closing said ports, a .rigid element connecting said valve means together into a unitary structure, an exterior valve operating member having a part extending through one of said ports and secured to the valve means acting to close said port, said operating member adapted to open one port while closing the other, the valve means alternately serving in their closed positions as fulcrums for said operating member, said member mounted so that for the same amount of movement it operates the valve means for the air admission port at a faster rate than the valve means for the vacuum admission port.

JESSE B. BROWN. 

